The present invention relates to a mooring device for holding up a dump body of a truck in a raised position for truck maintenance purposes and the like.
When making repairs, performing routine service or maintenance or doing other work on a dump truck, it is frequently desirable to put the dump body in a raised position in order to make access to certain components located beneath the dump body easier. Various techniques have been employed in the past for holding a dump body of a truck in its raised position when repairs or routine maintenance are being performed on the truck. One technique employed in the past is disclosed in U.S. Pat. No. 3,955,851 for a xe2x80x9cStopper Device for Use in Dump Truck""s Vessel,xe2x80x9d issued May 11, 1976 to Haruhiko Umeda et.al. that comprises a wire rope connected to the rear end portion of the dump body and the rear axle housing of the truck.
One problem with prior devices, such as the preceding, is that as trucks became larger, particularly the very large off-highway trucks employed at mines, the dump bodies became heavier and the hydraulic down force exerted by the dump body hoist system has increased. To accommodate the increase in weight or in hydraulic down force, larger diameter steel cable had to be used. However, large steel cable is very stiff and it can become impractical for one person to manipulate and hook up if the cable becomes twisted or bent to any degree.
The use of multiple cables can reduce this effort because each cable is smaller and more flexible, thereby making it possible for one person to hook the cables up. However, if the truck is setting on uneven ground or the truck body itself becomes twisted, the load exerted by the body when being held in its raised position may be exerted wholly on one of the cables because such prior devices could not accommodate the magnitude of the dimensional variations that can occur. This could cause this single load bearing cable to be overloaded and break.
The present invention is directed to overcoming one or more of the problems encountered in the use of prior art devices for maintaining a dump body of a truck in a raised position.
In accordance with one aspect of the present invention, a mooring device is provided for maintaining a dump body of a truck in a raised position. The truck has a chassis with the dump body pivotally mounted on the chassis about a transverse pivot axis for movement between a lowered position and a raised position. The mooring device includes a pair of laterally spaced apart and generally parallel tension members. Each tension member is attached between one of a first set of mooring points on the chassis and one of a second set of mooring points on the dump body. Each tension member is also capable of carrying a high tensile load sufficient to maintain the dump body in its raised position. The mooring device also includes a load distribution mechanism that contains one of the first and second sets of mooring points. The load distribution mechanism is constructed with a capacity to accommodate a sufficient amount of dimensional variation to ensure that the tension members are equally loaded when said mooring device is being employed so as to prevent one of the tension members from carrying a substantially greater tensile load than the other tension member.